A Midlands MEP has revealed she is Britain's first "sex change parliamentarian", having undergone gender reassignment surgery more than 20 years ago.

In a new autobiography about her political journey, Nikki Sinclaire, 45, writes for the first time about her "great secret" of growing up as a boy.

The We Demand A Referendum Now MEP for the West Midlands said she does not want her past to stand in the way of her ambition to become a cabinet minister at Westminster.

In an interview with the Sun on Sunday she said: "I don't want my past to overshadow it and believe my constituents will continue to support me.

"I feel passionately that true equality happens only when your colour, creed, gender or sexuality is not a label used next to your name. We are not there yet."

She told the newspaper how she suffered depression throughout her teenage years and "knew she was different" before undergoing the operation at the age of 23.

The foreword for her book, Never Give Up, tells how until now only Miss Sinclaire's family and close friends were aware of her past.

"There was one great secret that Nikki never shared with anyone other than her close friends and family," it reads.

"Hers is a powerful personal story. Yet she insists it is only one facet of her life, and though it tormented her childhood and teenage years, it is one that no longer dominates her or her future.

"As the first 'sex change' parliamentarian in Britain, Nikki Sinclaire has made history. But she is likely to be far happier, in the future, being known less as a statistic than for her conviction politics."

Miss Sinclaire's revelation has won her a lot of support on her Twitter feed.

Miss Sinclaire also writes about her rocky start in the European Parliament and her determination for an EU referendum.

She was elected as an MEP in 2009 for Ukip but was kicked out of the party months later for refusing to sit with the eurosceptic group Europe of Freedom and Democracy (EFD) which Ukip joined at the European Parliament.

She said she quit the EFD because it contained "extreme elements", including people with "openly homophobic opinions".

West Midlands Police arrested her in February last year as part of a probe into allowances and expenses but she denies the allegations, she told the newspaper. She remains on bail.